《Asymmetric construction of acyclic quaternary stereocenters via direct enantioselective additions of α-alkynyl ketones to allenamides》 was written by Wang, Jiawen; He, Faqian; Yang, Xiaoyu. Application of 1530-32-1 And the article was included in Nature Communications in 2021. The article conveys some information:
Acyclic quaternary stereocenters are widely present in a series of biol. active natural products and pharmaceuticals. However, development of highly efficient asym. catalytic methods for the construction of these privileged motifs represents a longstanding challenge in organic synthesis. Herein, an efficient chiral phosphoric acid catalyzed direct asym. addition of α-alkynyl acyclic ketones with allenamides has been developed, furnishing the acyclic all-carbon quaternary stereocenters with excellent regioselectivities and high enantioselectivities. Extensive and detailed exptl. mechanistic studies were performed to investigate the mechanism of this reaction. Despite a novel covalent allyl phosphate intermediate was found in these reactions, further studies indicated that a SN2-type mechanism with the ketone nucleophiles is not very possible. Instead, a more plausible mechanisml involving the elimination of the allyl phosphate to give the α,β-unsaturated iminium intermediate, which underwent the asym. conjugate addition with the enol form of ketone nucleophiles under chiral anion catalysis, was proposed. In virtue of the fruitful functional groups bearing in the chiral products, the diverse derivatizations of the chiral products provided access to a wide array of chiral scaffolds with quaternary stereocenters. In addition to this study using Ethyltriphenylphosphonium bromide, there are many other studies that have used Ethyltriphenylphosphonium bromide(cas: 1530-32-1Application of 1530-32-1) was used in this study.
Ethyltriphenylphosphonium bromide(cas: 1530-32-1) is a phase transfer catalyst, used to accelerate the cure of phenolic-based epoxy resins, certain fluoroelastomer resins and thermosetting powder coatings. It is also used as catalysts in the synthesis of certain organic compounds and as a pharmaceutical intermediate.Application of 1530-32-1
Referemce:
Bromide – Wikipedia,
bromide – Wiktionary